Toothed piddler belts

ABSTRACT

A belt piddler having two vertically mounted endless belts having contiguous vertical sections to form a means for gripping a continuous advancing length of material is modified to improve operability by grooving the surfaces of the belts which contact each other. The grooves are across the entire width of each belt and preferably are continuous.

United States Patent [191 Crocker TOOTHED PIDDLER BELTS [75] Inventor:Tallie Joseph Crocker, Waynesboro,

[73] Assignee: E. l. duPont de Nemours and Company, Wilmington, Del.

[22] Filed: Oct. 6, 1972 [21] Appl. No.: 295,663

[52] US. Cl. 226/172 [51] Int. Cl B65h 17/34 [58] Field of Search19/153, 244, 115, 129,

19/66 R; 198/165; 226/172; 28/1 CF I [56] References Cited UNITED STATESPATENTS 463,110 11/1891 Dryden 198/165X [451 Apr. 30, 1974 2,805,7659/1957 Saum 226/172 3,341,899 9/1967 Marriner 19/66 R FOREIGN PATENTS ORAPPLICATIONS 634,929 3/1950 Great Britain 19/70 Primary Examiner-RichardA. Schacher [57] ABSTRACT I A belt piddler having two vertically mountedendless belts having contiguous vertical sections to form a means forgripping a continuous advancing length of material is modified toimprove operability by grooving the surfaces of the belts which contacteach other. The grooves are across the entire width of each belt andpreferably are continuous.

3 Claims, 3 Drawing Figures PATENTEBAPR 3 0 1914 FIG. I

BACKGROUND OF THE INVENTION This invention relates to apparatus forreceiving and distributing a moving, wet filamentary tow or othercontinuous length of fibrous material. More particularly, it relates toan apparatus for receiving running lengths of wet tow at high speed anddelivering the wet tow smoothly to a can or other stationary containerpositioned beneath the apparatus.

In the manufacture of acrylic tows or other tows of synthetic filaments,it is frequently desired to subject the tow to treatment with water oran aqueous bath during or just after spinning and then to deliver therunning wet tow at high speed into a large can or other suitablecontainer for intermediate storage. In delivering the tow into acollection container, it is desired to use a simple belt piddler such asthe one disclosed by Saum et al., in U. S. Pat. No. 2,805,765,consisting of two endless belts running vertically in close proximity.

Although a belt piddler is fairly satisfactory for handling a moving towwhen the tow is merely moist, difficulties arise when the tow is quitewet. When the tow is wet, it tends to cling to one of the belts andfollow the belt around to a point at which it wraps around the belt.Because of the high rate of product throughput at each piddler andbecause it is not customary to man each piddler continuously, theresulting process discontinuity is very wasteful even if it occurs onlyonce each day. Accordingly, to avoid this problem, it is usually foundnecessary either to remove most of the water from the tow or to employ apiddler other than a belt piddler.

' SUMMARY OF THE INVENTION The present invention provides an improvedapparatus for piddling moving continuous lengths of wet fibrousmaterial. The apparatus comprises a belt piddler having two endlessbelts mounted in vertical spatial proximity on driving and tension rollsand adapted for receiving a continuous length of fibrous material fromabove and delivering said material to a designated point beneath thepiddler. The improvement in the apparatus consists in the belts in thepiddler being provided with a multiplicity of grooves transverse to thedirection of the travel of the belts and on the surface of the beltswhich contacts the fibrous material.

By employing the apparatus of the invention in which the surfaces areprovided with grooves transverse to the direction of the travel of thebelt on the surfaces which contact the fibrous material, it is foundthat very wet tows and other continuous lengths of textile fibermaterial may be handled with only an extremely low incidence of wrappingof the tow around the belt.

The endless belts should be somewhat wider than the width of the movingcontinuous lengths .of fibrous material. The two belts preferably havethe same width. In each grooved belt, the grooves in the belt shouldcross most of the area of the surface of the belt which is contacted bymoving continuous length of fibrous material. Preferably, the groovesare continuous across the entire Width of the belt.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevation view of a beltpiddler in accordance with the present invention.

the belt at point A of FIG. 1.

FIG. 2 is an enlarged view of the profile of the belt at point A of FIG.1, and

FIG. 3 is an enlarged view of an alternative profile of DETAILEDDESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, thebelt piddler is generally designated by reference numeral 12 andcomprises two belts designated by reference numerals l and 2, which aremounted to be in close proximity and form a nip of some length during apart of their respective travel. Belt 1 is mounted on rolls 3 and 4,being driven by drive roll 3. Belt 2 is similarly mounted on rolls 5 and6, being driven by drive roll 5. Rolls 4 and 6 are air loaded tensionrolls. The belts are made to contact or almost contact each other by theplacement of these rolls and by the use of idler rolls 7 and 8 overwhich belt 1 runs and idler rolls 9 and 10 over which belt 2 runs. Idlerroll 9 is an air loaded compression roll. All of the rolls are mountedon plate 18, drive rolls 3 and 5 being driven at the same surface speedbp means of gears 11 mounted behind the plate.

The moving tow 13 is fed from a source-(not shown) over roll 14 to andthrough guide 15 and thence to belt piddler 12. It first passes into theupper nip 20 of the belts and is carried between beltsl and 2 to thelower nip 21, at which point it is discharged'from the belts into atraverse guide 16 which isan oscillating funnel or boot. Under thisguide 16 is a can or container 17 in which the tow 13 is deposited. Thetraverse guide is mounted in gimbals 19 below the belt. The container 17may be rotated or traversed as desired, and when filled, is removed andreplaced by an empty container in accordance with conventional practice.

In accordance with the invention, the belts have grooves transverse tothe direction of travel of the belt provided in their outer surface 22,which is the surface which contacts the moving continuous length offibrous material. An enlarged view of the profile of one embodimentofthe grooved belt is shown in FIG. 2. In this embodiment, the belts havea saw-toothed profile at their outer. face and the grooves are V-shaped,meeting each other at the surface so that the surface has no flatportion.

An enlarged view of the profile of another embodiment of the groovedbelt is shown in FIG. 3. In this embodiment, the belts have a profile inwhich the grooves have sloping sides and flat portions at the bottoms ofthe grooves, being spaced to provide flat portions on the surface of thebelt equal in length to the flat portions at the bottoms of the grooves.

The outer surfaces of the belts may also have other profiles providinga-multiplicity of groovestransverse to the direction of travel of thebelt. For instance, the grooves may have vertical walls separated byflat portions on the surface of the belt and flat portions at thebottoms of the grooves. The profile of the outer surface of the beltsmay also be a sinuous curve. Other configurations of the profile of theouter surface of the belt will be readily apparent.

The belts employed in the apparatus of this invention may be made ofrubber or a tough, resilient, synthetic polymer such as polyvinylchloride. Other equivalent materials may be used to form the maincomposition of the belt, with or without a surface coating as desired.For additional strength and durability, the belts may be reinforced witha fabric of polyesterfibers, cotton, rayon, or other suitable fibers.Other suitablev reinforc ing structures within the belt may be used.

In FIG. 1, the direction of belt 2 has a greater deviation from verticalas it approaches tension roll 6 than the direction of belt 1 as itapproaches tension roll 4. The more nearly vertical direction of belt 1is helpful under some circumstances in assisting a vertical discharge ofthe continuous length of fibrous material from the belts. However, ifpreferred, tension rolls 4 and 6 may be mounted in such positions thatthe belt directions have the same deviation from vertical as theyapproach the bottom.

As employed herein, the term continuous length of fibrous material ismeant to include not only tows of continuous filaments but also ropes oryarns of continuous filaments as well as slivers of staple fibers andother equivalent fibrous structures. The advantages of employing thegrooved belts of the invention are most readily observed in handlingcontinuous lengths of tibrous materials which are quite wet, i.e.,containing an amount of water equal to at least half of the dry weightof the continuous length of fibrous material. However, the piddlersemploying the grooved belts may also be used for handling dry movingcontinuous lengths of tibrous material, or continuous lengths of suchmaterial which are only somewhat moist.

In operation, a piddler having the design shown in FIG. 1 is equippedwith two grooved belts comprised of V 70 percent polyvinyl chloride byweight reinforced with 30 percent by weight of a fabric of polyesterfiber.

Each belt has an outside surface, or fiber-contactingsurface, having asaw-toothed profile such as that depicted in FIG. 2. Each belt is 0.15inch thick, measured between the inside surface of the belt and thefurthermost points of the outside surface of the belt; and the distancebetween peaks of the saw-toothed profile is 0.15 inch. The depth of thegrooves (vertical distance between peaks and valleys) is 0.05 inch. Thebelts are 70 inches long and 6.5 inches wide. The piddler is employed toreceive tows of spun acrylonitrile polymer filaments containing about 115,000 filaments per tow and having a moisture content of percent water,based on the weight of the dry tow. The individual filaments have adenier per filament of about 10. The moving tow is taken up by thepiddler at the rate of about 400 yards per minute and is dischargedvertically at the same rate through an oscillating funnel into acontainer positioned below the piddler. During a prolonged test of thepiddler, it is observed that the incidence of wraps around one of thebelts of the piddler attributable to malfunction of the piddler is fewerthan one wrap per month. y

In a similar run made for comparison purposes, a piddler havingconventional, ungrooved belts is employed to handle tows ofacrylonitrile polymer filaments of the same size and same moisturecontent, at the same rate of delivery and discharge. The conventionalbelts are made of polyvinyl chloride reinforced by fabric and have asomewhat roughened surface comprising an embossed pattern ofdiamond-shaped indentations having a depth of 0.010 inch and having eachside of the diamond measuring approximately 5/64 of an inch. Inemploying these belts, it is observed that the incidence of wrapsattributable to malfunction of the piddler is at the rate of more thanone wrap per day.

What is claimed is:

1. In an apparatus for piddling continuous moving lengths of wet fibroustow including a belt piddler having two vertically mounted endless beltshaving vertical sections with smooth surfaces in contiguous relation toform a means for gripping said material and advancing it to a designatedpoint beneath the piddler, said wet tow having a tendency to wrap aroundone of the belts, the improvement comprising: the surfaces of said beltsin contiguous relation having a plurality of transverse grooves therein,whereby the incidence of wraps of said wet tow around one of said beltsis reduced.

2. The apparatus of claim 1, said grooves being across the entire widthof said belts.

3. The apparatus of claim 2, said grooves being continuous.

1. In an apparatus for piddling continuous moving lengths of wet fibroustow including a belt piddler having two vertically mounted endless beltshaving vertical sections with smooth surfaces in contiguous relation toform a means for gripping said material and advancing it to a designatedpoint beneath the piddler, said wet tow having a tendency to wrap aroundone of the belts, the improvement comprising: the surfaces of said beltsin contiguous relation having a plurality of transverse grooves therein,whereby the incidence of wraps of said wet tow around one of said beltsis reduced.
 2. The apparatus of claim 1, said grooves being across theentire width of said belts.
 3. The apparatus of claim 2, said groovesbeing continuous.